Railway-traffic-controlling apparatus



Dec. 20, 1927.

H. A. THOMPSON ET AL RAILWAY TRAFFIC CONTROLLING APPARATUS Filed Dec.1'1, 192s ENTORS Patented Dec. 20, 1927.

UNITED STATES 1,653,379 PATENT OFFICE.

etowrinn A. rzeiorarsonyor EUR-917G1 1, Ann CHARLES w. FAILOR, orrrrrsenn PnNnsYLvArtrA, A'ssrsnons TO THE Union 'swIr'cH & sIGNAI.COMPANY, or swIssvALn, PENNS-:"LVAE=IEA, A con'PonATIoN OF PENNSYLVANIA.

nAILW Y-rnArrro-oonrnoLLnve APPARATUS.

Application filed December 11, 1926. Serial No. 154,093.

Our invention relates to railway traliic controlling apparatus, andparticularly to apparatus of the type comprising train carried governingmeans cooperating with train controlling devices located at intervalsalong the trackway and controlled in accordance with traffic conditions.More particularly our present invention relates to the track'way portionof such apparatus.

Vi e will describe one form of trackway apparatus embodying ourinvention, and will then point out the novel features thereof in claims.

The accompanying drawing is a diagrammatic view illustrating one form oftrackway'apparatus embodying our invention.

Referring to the drawing, the reference characters 1 and 1 designate thetrack rails of a stretch of railway track over which traflic normallymoves in the direction indicated by the arrow. These rails are divided,by means of insulated joints 2, into a plurality of successive tracksections AB, B-C, etc. Each such track section is provided with a sourceof track circuit current here shown as a track battery designated by thereference character F with an exponent corresponding to the location andconnected across the rails adjacent thee'xit end of the section throughthe usual impedance 9. Each track section is also provided with a trackrelay designated by the reference, character R with an exponentcorresponding to the location and connected across the rails adjacentthe entrance end of the corresponding section. Associated with eachtrack relay R are a home relay and a distant relay designated by thereference characters H and. D, respec tively, with exponentscorresponding to the location. Under normal conditions, relay H is heldin its energized condition by virtue of a stick circuit including itsown front contact and a front contact of an adjacent track relay R.Referring particularly to the apparatus located at point A, the stickcircuit for relay H may be traced from a suitable source of energy suchas a battery E", through wire 11, front contact 12 of re lay R wires 13and 14, front contact 15 of relay H wire 16, winding of relay H andwires 17 and 18, back to battery E Each section is also provided withaslow acting checking relay designated by the reference character G withan appropriate exponent and controlled in a manner which will beexplained hereinafter.

The circuit for relay D may be traced from battery E through wire'll,front contact 12 ofrelay R wires l3, l4 and 19, front contact 20 ofrelay H wire 21, winding of relay D wire 22, backcontact- 23 of checkingrelay G Wire 24, front contact 25 of relay H fandwires 26 and 18, backto battery E Relay D is therefore energized only when relays R H and Hare energized and when relay G is deenergized.

The control of each of the remaining di tant relays D is similar to thatjust described for relay D Each track section is also provided with atrackway signal designated by the reference character S with an exponentcorresponding to the location. These signals may be of any suitable typeand are here illustrated as threeindication light signals eachcomprising three light units 6, 7 "and 8, arranged when energized toindicate stop, caution and proceed, respectively. Each signal S iscontrolled by the associated relays R, H and D, over circuits which willnowbe described.

Referring particularly to signal S when relays R H and D are allenergized, a circuit is closed from secondary 37 oftransformer T throughwire 41, front contact 42 of relay 3*, wire 43, front contact 44 ofrelay H wire 45, front contact 46 of relay D wire 47, unit 8 of signal Sand wire 52, back to secondary 37 of transformer T. The primary 38 oftransformer T is supplied with alternating current from secondary 39 ofa transformer Qflthe primary 40 of which is constantly supplied withalternating current from a suitable source such as an alternator M overline wires 10 and 10 WVhen the circuit .just traced is closed,therefore, unit 8 of signal S is lighted to indicate proceed. The signalS is also provided with a caution circuit passing from secondary 37 oftransformer T through wire 41, front contact 42 of relay R wire 43,front contact 44 of relay H wire 45, back Contact 46 of relay D5, wire48, unit 7 of signal S and wire 52 back to secondary 3 7'of transformerT NVhen this circuit is closed, unit 7 of signal S is lighted toindicate caution. The stop unit 6 of signal S is provided withonecircuit which passes from secondary '37 of transformer T through wire41, front contact 42 of relay R wire 43, back contact 14; of relay I'Iwires 49 and 50 unit 6 of signal S", and wire 52 back to secondary 37 ofponent and located a short distance in rear lit of the entrance end ofthe corresponding section. In the present embodiment of our invent-ioneach inductor K comprises a magnetizable core provided with meansresponsive to trafiic conditions for varying the effective reluctance ofthe core.- The inductors K are suitable for co-operation with traincarried governing means which is responsive to the effective reluctanceof the cores of the inductors. In systems of this character it iscustomary to arrange the train governing means to give a proceedindication when passing an inductor having a comparatively higheffective reluctance and to give a stop indication on board the trainwhen the train passes an inductor having a comparatively low effectivereluctance.

The variation in the effective reluctance of the inductor cores isaccomplished by providing each inductor with one or more windings whichare at times shunted in re-' sponse to traffic conditions. Since theoperation of the train governing means depends upon the change ininductor reluctance due to the shunting effects of these windings, it isdesirable to afford a check against short circuits or open circuits inthe inductor windings or in the circuits associated therewith. In ourpresent: invention we accomplish this result by providing the core 5 ofeach inductor K with. two windings 3 and 4, both of which windings areshunted when it is desirable to give a proceed indica tion on board thetrain. The windings 3 and 4 of each device K are inductively related andwe utilize the transformer action between these windings to check theintegrity of the circuits.

As shown in. the drawing, the section to the right of point C isoccupied by a train V so that track relay It is de-energized therebytie-energizing relays H" and 1). Signal S" therefore indicates stop.Relays R and H are energized but relay D is de energized, the circuitfor the latter relay being" open at front contact of relay H and signalS therefore indicates caution. Relays It", H and D are all energized andsignal S therefore indicates proceed., Considering now the shuntingCll'. cuits for the inductors K, it will be seen from the drawing thatboth windings of inductor K are shunted by front contacts of distantrelay D, the shunting circuit for winding 4 passing from the right-handterminal of this winding, through wires 27 and 28, front contact 29 ofrelay D and wires 30 and 31, back to winding The shunting circuit forwinding 3 passing from the right-hand terminal of this winding, throughwires 32 and 33, front contact .34 ofrelay D and wires 35 and 36 back tothe stick circuit for relay H is open at its own front contact 15. V p

Vith relay H de-energized and relayIi.

energized, alternating current is supplied to winding 4; of inductor Kfrom secondary 53 of transformer P the primary 54 of i which isconstantly supplied with alternating current from secondary 39 oftransformer Q the circuit for suchcurrent passing from secondary 53 oftransformer P? through wire .35, front contact 56 or relay B wires 57and 27, *inding f of inductor 1 wires 31 and 58, back contact of relayII" 4 iii? and wire 60 back to secondary 53 of trans" former P. At thesame time the checking relay G is connected with winding 3 of inductor Kthe circuitpassing from one terminal of winding 3, through wires 32 and61, back contact 62 of relay H wire (33, winding of relay G and wires 64and 36 back to winding 3 of inductor K The current supplied to windingst of inductor K induces in winding 3 an electromotive force whichsupplies current to relay G thereby energizing that relay. As soon asfront contact 66 of relay G" closes, current from battery E flowsthrough wire 11, front contact 12 of relay R wires B and (i5, frontcontact ($6 of relay ti. wire 67, winding of relay H, and wires 17 and18 back to battery It". Relay H therefore becomes energized, opening itsback contacts and con ipleting, at front contact 15 thereon.

the stick circuit for relay H" by means of which the relay issubsequently maintained in its energized condition irrespective of thecondition of relay G". The opening of back cont-act 62 of relay Hinterrupts the circuit for relay CT so that the latter relay againbecomes tie-energized. Furthermore the opening of back contact-'59 ofrelay H dis connects secondary of transformer P from winding st-ofinductor K so that as soon as relay H lJG'ZOIHBS energized,-the inductorK is deprived of alternatingcurrent and relay G becomes de-energized,thereby restoring the apparatus to its normal con dition. Relay Gtherefore remains -de-energized until. the next time a train moves outof the section to the right of point C. It follows that when the homerelay H for the section next in advance becomes energized, relay D maybe energized over back cont-act 2S of relay G It should be particularlypointed out'that by requiring the energization of relay G to pick up theassociated home relay H when a train leaves the associated section, aposit ve check is made upon the windings of theadjacent inductor K, andthat this check insuresnot'only that there are no breaks in the inductorwindings or their associated circuit-s but also that there are no shortcircuits 1n the shunting circuits for either of the windings of theadjacent inductor K.

Such short circuit would prevent the energization of relay G and,consequently, would prevent the closing of the pick-up circuit for relayH when the train leaves the section. It will be manifest, therefore,that with apparatus embodying our invention, a dangerous conditioncannot arise due to a break or a short circuit in the windings of theinductor or in the circuits associated therewith, because any suchdefect would prevent the energization of the adjacenthome relay andwould therefore hold at stop the signal controlled by such home relay,and would hold at caution the signal next in rear.

'Althongh we have herein shown and described only one form of railwaytrafific controlling apparatus embodying our invention, it is understoodthat various changes and modifications may be made therein within thescope of the appended claims without departing from the spirit and scopeof our invention.

Having thus described our invention, what we claim is:

1. In combination, with a section of rail way track, a first relay, asignal controlled by the first relay, a checking relay, a trackwaydevice comprising a winding, means for energizing the checking relay ifand only if the winding is intact, a circuit for the first relayincluding a front contact of the checking relay, and means including afront contact of the first relay for removing the checking relay fromthe control of the first relay.

2. In combination, a section of railway track, a relay, a signal for thesection controlled by the relay, a trackway device com prising twoinductively related windings, means for at times shunting both saidwindleaves the section to energize the relay,

ings, means controlled by said windings and effective for a briefinterval. after a train and other ,means for subsequently maintainingthe relay in .itsenergized condition.

3. In combination, a section of railway track,.a relay, a signal for thesection controlled by the relay, atrackway device co1nprising twoinductively related windings, means for shunting both said windings whenthe relay is energized, means effective for a. brief interval oftimeafter a train leaves the stretch to supply alternating current to onesaid winding, means controlled by the elect-romotive force induced inthe other winding by suchcurrent for energizing the relay, and meansforsubsesucntly maintaining the relay in its energized condition afterthe windings are shunted.

4. In combination, a section of railway track, a first relay, a signalcontrolled by the first relay, a second relay, means effective when thefirst relay is tie-energized and operating when a train leaves thesection to energize the second relay, means including a front contact ofthe second relay for energizing the first relay, and means forsubsequently maintaining the first relay in its energized condition aslong as the section is unoccupied.

5; In combination, a section of railway track, a first relay, a signalfor the section controlled by the first relay, a trackway de vicecomprising two inductively related windings, means controlled by thefirst relay for supplying alternating current to one of said windings, asecond relay at times connected with the other winding, means controlledby said second relay for energizing the first relay, means forsubsequently removing the second relay from the control of the firstrelay, and means controlled by the first relay for at times shuntingboth said windings.

6. In combination, a section of railway track, a track relay for suchsection, a home relay, a checking relay, a trackway device comprisingtwo inductively related windings, means including a front contact of thetrack relay and a back contact of the home relay for supplyingalternating current to one of said windings, means including a backcontact of the home relay for connecting the checking relay with theother said winding, a pick-up circuit for the home relay including afront contact of said checking relay and a front contact of the trackrelay, a stick circuit for the home relay including its own frontcontact and a front contact of the track relay, and a signal for saidsection controlled by the home relay.

7. In combination, a plurality of successive sections of railway track,a track relay for each section, a home relay and a distant relay foreach section, a signal for each section controlled by the associatedhome relay and distant relay, a trackway device for each sectioncomprising two inductively related windings, a checking relay for eachsection, means for supplying alternating current to one winding of eachtrack way device when the adjacent track relay is energized and when theadjacent home relay is de-energized, means for connecting each checkingrelay with the remaining winding of the adjacent trackway device whenthe home relay associated with such checking relay is de-energized, apick-up circuit for each home relay including a front contact of theassociated checking relay and a front contact of the associated trackrelay, a stick circuit for each home relay including its own frontcontact and a front contact of the associated track relay, a circuit foreach distant relay including front contacts of the associated home relayand the home relay for the section next in advance and a back contact ofthe associated checking relay, and means controlled by each distantrelay for shunting both windings of the associated tr'ackway device.

8. In combination with a section of railway track, a first relay, asignal controlled by the first relay, a second relay, means for at timesclosing the second relay for a brief interval of time, a pickup circuitfor the first relay controlled by the second relay,

and a stick circuit for the first relay.

9. In combination with a section of railway track, a first relay, asignal controlled by the first relay, a second relay, means for at timesclosing the second relay for a brief interval of time, a pickup circuitfor the first relay controlled by the second relay, and means forsubsequently maintaining the first relay in its energized conditionirrespective of the condition of the first relay.

10. In combination, a section of railway tr'ack, a first relay, a signalcontrolled by the first relay, a second relay, a trackway devicecomprising a winding, means for at times energizing the second relay ifand only if the winding is intact, a pickup circuit for the first relaycontrolled by the second relay, and a stick circuit for the first relay.

11. In combination, a section of railway track, a home relay arranged tobe de-energized when the section is occupied, a signal controlled by thehome relay, a checking relay, a trackway device comprising a winding,means including a back contact of the home relay for energizing thechecking relay when a train leaves the section if and only if saidwinding is intact, a pickup circuit for said home relay including afront contact of the checking relay, and a stick circuit for the homerelay.

In testimony whereof we afiix our signatures. V

HOWARD A. THOMPSON. CHARLES W. FAILOR.

DISCLAIMER 1,653,379.H0ward A. Thompson, Edgewood Borough, and CharlesW. Failor, Pittsburgh, Pa. RAILWAY-TRAFFIC-CONTROLLING APPARATUS. Patentdated December 20, 1927. Disclaimer field June 22, 1933, by theassignee, The Union Switch d2: Signal Company.

Hereby enters the following disclaimer, to wit: Your petitioner herebydisclaims the subject matter of claims 8 and 10.

[Ofllcial Gazette July 18, 1933.]

